Device and method for setting therapeutic parameters for an infusion device

ABSTRACT

Embodiments are directed to infusion devices, systems, and methods to detect a capacity of a collapsible fluid reservoir of an infusion cartridge and/or a volume of a fluid disposed in the collapsible fluid reservoir or some other parameters of the infusion cartridge, and setting corresponding therapeutic parameters of an infusion device. Embodiments may include, obtaining data on the volume of fluid in the collapsible fluid reservoir, analyzing the obtained data to determine the setting of therapeutic parameters, and setting one or more therapeutic parameters of an infusion device.

BACKGROUND

There are many applications in academic, industrial, and medical fields,as well as others, that benefit from devices and methods that arecapable of accurately and controllably delivering fluids, includingliquids and gases that have a beneficial effect when administered inknown and controlled quantities. Such devices and methods areparticularly useful in the medical field where treatments for manypatients includes the administration of a known amount of a substance atpredetermined intervals. As the number of commercially availabledelivery systems increase, different types of medication holdingcartridges or infusion cartridges are made available.

Insulin-injecting pumps have been developed for the administration ofinsulin for those suffering from both type I and II diabetes. Continuoussubcutaneous insulin injection and/or infusion therapy with portableinfusion devices has been adapted for the treatment of diabetes. Suchtherapy may include the regular and/or continuous injection or infusionof insulin into the skin of a person suffering from diabetes and offeran alternative to multiple daily injections of insulin by an insulinsyringe or an insulin pen. Such pumps can be ambulatory/portableinfusion pumps that are worn by the user that may use replaceablecartridges. Examples of such pumps and various features that can beassociated with such pumps include those disclosed in U.S. patentapplication Ser. No. 13/557,163, U.S. patent application Ser. No.12/714,299, U.S. patent application Ser. No. 12/538,018, U.S.Provisional Patent Application No. 61/655,883, U.S. Provisional PatentApplication No. 61/656,967 and U.S. Pat. No. 8,287,495, each of which isincorporated herein by reference.

To discriminate between the large varieties of available cartridges,numerous coding schemes have been developed for recognizing thedifferent types of cartridges in order that the delivery of a specificamount of a medicament is allowed by a delivery device. Generally,available systems are limited by the variety of coding schemes they canhandle. Existing systems may also be limited by the scope of adjustmentsmade, as a result of obtaining cartridge identification information

Therefore, devices and methods capable of automatically and reliablyrecognizing a wide variety of cartridges, and implementing usefuladjustments to the delivery systems are needed.

SUMMARY

Some embodiments include a method for detecting a capacity of a drugdelivery reservoir of an infusion cartridge and setting therapeuticparameters of an infusion device setting based on the detected capacity.The method may include obtaining data on the capacity of the drugdelivery reservoir, analyzing the obtained data on the capacity of thedrug delivery reservoir, determining the setting of therapeuticparameters, and setting one or more therapeutic parameters of aninfusion device based on the capacity data.

Some embodiments include a method for detecting a capacity of acollapsible fluid reservoir in an infusion cartridge and settingtherapeutic parameters of an infusion device such as a portable orambulatory infusion pump. The method can include obtaining data on thecapacity of the collapsible fluid reservoir, analyzing obtained data onthe capacity of the collapsible fluid reservoir to determine the settingof therapeutic parameters of the infusion device, and setting one ormore therapeutic parameters of the infusion device. The therapeuticparameters can include a basal rate range, a bolus volume range, a maxbolus volume range, and insulin sensitivity. Data on the capacity of thecollapsible fluid reservoir can be obtained by reading optical indicia,reading signals from a radio frequency identification (RFID) tag orsensing positions of a plurality switches coupled to mechanical sensorsof the infusion device that are registered with surface grooves on theinfusion cartridge indicating.

Some embodiments include a method for detecting a volume of a fluiddisposed in a collapsible fluid reservoir of an infusion cartridge andsetting therapeutic parameters of an infusion device. The methodincludes obtaining data on the volume of the fluid disposed in acollapsible fluid reservoir; analyzing obtained data on the volume ofthe fluid to determine the setting of therapeutic parameters; andsetting one or more therapeutic parameters of an infusion device. Thetherapeutic parameters can include a basal rate range, a bolus volumerange, a max bolus volume range, and insulin sensitivity. Data on thevolume of the fluid disposed in the collapsible fluid reservoir can beobtained by taking a plurality of pressure sensor readings, which areindicative of the volume of the fluid disposed in the collapsible fluidreservoir.

Some embodiments include an infusion device such as a portable infusionpump configured for detecting the capacity of a drug delivery reservoiror a volume of fluid disposed inside an infusion cartridge that may beattached to it, and for setting therapeutic parameters for the infusiondevice. The infusion cartridge may include a delivery mechanism foreffectuating the delivery of fluid. The delivery mechanism may includean axial bore. A first and a second inlet port may be in fluidcommunication with an interior volume of the axial bore. The secondinlet port may be axially spaced from the first inlet port. At least oneoutlet port, which may be axially spaced from the inlet ports, may alsobe in fluid communication with the interior volume of the axial bore. Aspool may be disposed within the axial bore. The spool may be axiallytranslatable within the axial bore and may form a constrained variablevolume in conjunction with an interior surface of the axial bore. Theinfusion cartridge may also include a drug delivery reservoir forstoring fluid. The drug delivery reservoir may include an interiorvolume that may be in fluid communication with the first inlet port. Theinfusion device may further include an infusion pump. The infusion pumpmay include a drive mechanism which may be operatively coupled to thespool. The infusion pump may be configured to impart controlled axialmovement to the spool and may translate the constrained variable volumefrom the inlet ports to the outlet port. The infusion device may alsoinclude a processor. The processor may determine the capacity of thedrug delivery reservoir or the volume of fluid disposed in the drugdelivery reservoir and may set therapeutic parameters. The processor maybe coupled to a memory and it may be configured for receiving input datafrom the memory. The processor may use the input data for generatingtherapeutic parameters for the infusion device. The memory may beconfigured for receiving, storing and communicating input data to theprocessor. A display may be coupled to the processor. The display may beconfigured for displaying a request to a user for input data. Thedisplay may be further configured for receiving user input data inresponse to the request and for display, communicating that data to thememory.

Certain embodiments are described further in the following description,examples, claims, and drawings. These features of embodiments willbecome more apparent from the following detailed description when takenin conjunction with the accompanying exemplary drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts an embodiment of an interchangeable pump assembly.

FIG. 2 depicts an embodiment of an infusion pump having an infusioncartridge embodiment coupled thereto.

FIG. 3 depicts a block diagram representing an example of some elementsof the infusion pump of FIG. 2.

FIG. 4 depicts a perspective view of the infusion pump embodiment ofFIG. 2 which can includes a graphic user interface with touch screencapability.

FIG. 5 is an exploded view of the infusion cartridge and infusion pumpembodiment of FIG. 2 with the infusion cartridge removed from theinfusion pump.

FIG. 6 is a schematic view partially cut away depicting some internalcomponents of the infusion pump embodiment of FIG. 2 and the disposableinfusion cartridge embodiment.

FIG. 7 is an elevation view in partial section of a delivery mechanismembodiment of the infusion cartridge of FIG. 6 coupled to a drivemechanism embodiment.

FIG. 8A is an elevation view of the infusion cartridge of FIG. 2depicting locations for indicia.

FIG. 8B is a partial exploded view of the infusion pump embodiment ofFIG. 5 with the infusion cartridge removed depicting locations ofvarious sensors.

FIG. 9 is a flowchart of a method for detecting a capacity of a drugdelivery reservoir of the infusion cartridge of FIG. 2 and for settingtherapeutic parameters in the infusion pump according to an embodimentof the present disclosure.

FIG. 10 is a flowchart of a method embodiment for obtaining dataregarding the capacity of the drug delivery reservoir of FIG. 2.

FIG. 11 is a flowchart of a method embodiment for obtaining data on avolume of a medicine disposed in the drug delivery reservoir of FIG. 6by using a pressure metering technique embodiment.

FIG. 12 is a flowchart of a method for obtaining data on a volume of amedicine disposed in the drug delivery reservoir of FIG. 6 by using apressure metering technique embodiment.

DETAILED DESCRIPTION

Disclosed herein are methods and devices for detecting the capacity of adrug delivery reservoir, or a volume of medicine disposed in the drugdelivery reservoir, and for setting therapeutic parameters of aninfusion device such as a portable or ambulatory infusion pump. Someinfusion device, system, and method embodiments discussed herein mayaccount for a wide range of variables in determining an amount ofmedicament, e.g. insulin, to be infused into a patient over a givenperiod of time. Further, some embodiments discussed herein may allow forrefined regulation of the amount of medicament delivered as well as thetime during which the medicament is delivered. Some embodiments mayinclude advances in the internal components and the control circuitry,as well as improvements in a user interface. The advances may allow foran accurate regulation of blood glucose levels. Although embodimentsdescribed herein may be discussed in the context of the controlleddelivery of insulin, delivery of other medicaments, including, forexample, glucagon, pramlintide, etc., as well as other applications arealso contemplated. Device and method embodiments discussed herein may beused for pain medication, chemotherapy, iron chelation, immunoglobulintreatment, dextrose or saline IV delivery, or any other suitableindication or application. Non-medical applications are alsocontemplated.

With regard to one particular indication, maintaining appropriate bloodglucose homeostasis is an important factor for promoting the length andquality of life of a diabetic patient. Different types of pumps providea user of a pump with various advantages, though some of them may bemutually exclusive. For example, a portable pump device having a largeoutput display can be easier to read and use when compared to a pumpdevice with a smaller output display. However, those pumps may also havea housing that is generally larger and may require a greater powerusage. Large and bulky ambulatory pump devices can be uncomfortable orunwieldy, contributing to problems with user compliance. For example, auser may be less likely to wear a larger pump device while sleeping, orwhen involved in certain activities. Smaller and more discreet pumpsystems can be more easily worn at night; however, they may not providefeatures that some patients may prefer for safety and convenience.

Some embodiments discussed herein may include an interchangeable pumpassembly that may provide a user with the flexibility and convenience toalternate between pump devices having various features and advantages atany given moment during a single treatment protocol. In some cases, asingle insulin cartridge may be switched between pump devices such as asmaller more discreet pumping device having fewer features and a largerpumping device having more features during a treatment with a singlecartridge without compromising the sterility and thus wasting thecartridge.

It should be noted that labels associated with operations describedbelow do not represent an order in a sequence; rather they are used onlyto uniquely identify each operation. The words, “loaded”, “written”, and“programmed” are used interchangeably when they refer to a processor ora memory device. The terms “pump” and “infusion pump” may be usedinterchangeably. The phrases “collapsible fluid reservoir” and “drugdelivery reservoir” may be used interchangeably. The phrases “infusioncartridge” and “fluid reservoir cartridge” may be used interchangeablyin this document. Also the phrases “sensor reading” and “sensor data”may be used interchangeably. Furthermore, as used herein, the term“fluid” shall mean a gas or a liquid, also the terms “fill” and“filling” shall mean increasing the amount of a fluid 84 in acollapsible fluid reservoir by some percentage of the total volume ofthe container up to 100%.

FIG. 1 depicts an embodiment of an interchangeable ambulatory infusionpump assembly 10 that may be used in pump embodiments configured todeliver a fluid or fluids from one or more reservoirs, which may be influid communication with a delivery mechanism thereof. The infusion pumpassembly 10 may include an infusion pump 12, a second infusion pump 14,an infusion cartridge 16 having an infusion set connector 18, andoptionally a glucose meter 20. The infusion cartridge 16 or the glucosemeter 20 may be functionally and interchangeably inserted in a firstreceiving slot 22 located in the infusion pump 12 and a second receivingslot 24 located in the second infusion pump 14. The infusion pump 12 mayhave a housing 26 that may be generally larger than a second housing 28of the second infusion pump 14. Similarly, the infusion pump 12 maygenerally include more operating features than the second infusion pump14. Some or all of the suitable features, dimensions, materials, andmethods of use of the infusion pump assembly 10 may be used orincorporated into any other infusion system, or components thereof,discussed herein. The interchangeability of infusion cartridgeembodiments herein may be discussed in the context of transferring aninfusion cartridge from the infusion pump 12 to the second infusion pump14, having features different from those of the infusion pump 12.However, all of the interchangeability features and methods associatedwith this type of transfer may also be applied to the transfer of aninfusion cartridge from the infusion pump 12 to a second infusion pump14 having the same features as the infusion pump 12.

FIG. 2 illustrates an embodiment of an ambulatory infusion pump system100 which includes the infusion pump 12 and the infusion cartridge 16.The housing 26 of the infusion pump 12 can be of any suitable shape andsize. For instance, the housing 26 may be extended and tubular, or inthe shape of a square, rectangle, circle, cylinder, or the like. Thehousing 26 may be dimensioned so as to be comfortably associated with auser, and/or hidden from view, for instance, within the clothes of auser. In some embodiments, the housing 26 of the infusion pump 12 mayhave a width of about 2 inches to about 5 inches, a height of about 1inch to about 3 inches and a thickness of about 0.25 inch to about 0.75inch; more specifically, the housing 26 may have a width of about 2.5inches to about 3.5 inches, a height of about 1.5 inches to about 2.5inches and a thickness of about 0.4 inches to about 0.8 inches. Thematerials of the housing 26 may vary as well. In some embodiments, thehousing of the infusion pump 12 may be a watertight, metal housing thatmay be taken apart for repairs.

The infusion pump 12 can include a user interface such as a graphic userinterface (GUI) 60. The GUI 60 may include an output/display 44. Theoutput/display 44 may vary as it may be useful for a particularapplication. The type of visual output/display may include LCD displays,LED displays, plasma displays and OLED displays. The output/display mayalso be an interactive or touch sensitive screen having an input device,such as a touch screen including a capacitive screen or a resistivescreen. In some embodiments, the output/display 44 of the full infusionpump 12 may be an OLED screen and the input may be a capacitive touchscreen. The infusion pump 12 may additionally include a keyboard oranother input device 40 known in the art for data entry, which may beseparate from the display. The output/display 44 of the infusion pump 12may also include a capability to operatively couple to a secondarydisplay device such as a laptop computer or a mobile communicationdevice, such as a smartphone or personal digital assistant (PDA).

The infusion pump 12 may have wired or wireless communication capabilityfor the sending and receiving of data as is known in the art. Thewireless capability may be used for a variety of purposes, includingupdating of any software or firmware for the processor of the device.The wireless communication capability may vary including, e.g., atransmitter and/or receiver, radiofrequency (RF) transceiver, WIFIconnection, infrared or Bluetooth® communication device. The wiredcommunication capability may also vary including, e.g., USB or SD portor flash drive port. In some embodiments, the infusion pump 12 may havea transmitter/receiver 32, such as a radiofrequency (RF) transceiver, asshown in FIG. 3 that may allow the infusion pumps to communicate withone another and may be used interchangeably without loss of data orinformation during an infusion protocol with an infusion cartridge 16.The infusion pump 12 may also act as a PDA or a controller to wirelesslycontrol the second infusion pump 14. For such an embodiment, data may betransferred between the controller of the infusion pump 12 and thesecond infusion pump 14 by radio signal, optical transmission or anyother suitable means. The first infusion pump 12 and the second infusionpump 14 may be used as stand-alone devices as well.

The infusion pump 12 may include a memory device 30. The memory device30 may be any type of memory capable of storing data and communicatingthat data to one or more other components of the device, such as theprocessor. The memory device 30 may be one or more of a Flash memory,SRAM, ROM, DRAM, RAM, EPROM and dynamic storage. For instance, thememory device 30 may be coupled to the processor and configured toreceive and store input data and/or store one or more template orgenerated delivery patterns. For example, the memory device 30 may beconfigured to store one or more personalized (e.g., user defined)delivery profiles, such as a profile based on a user's selection and/orgrouping of various input factors or input data. The user input data mayinclude one or more of blood glucose levels, a stress level, aphysiological condition, complexity of a meal to be ingested, and anactivity level. The user input data may include past generated deliveryprofiles; recommended delivery profiles; one or more traditionaldelivery profiles, e.g., square wave, dual square wave, basal rate andbolus profiles; and/or the like. In some embodiments, the memory device30 of the full-featured infusion pump device 12 may be up to about 10GB, more specifically, up to about 3 GB, even more specifically, about 1MB to about 200 MB. In some embodiments, the memory device 30 of thefull-featured infusion pump device 12 may be up to about 3 GB, morespecifically, up to about 500 MB, and even more specifically, about 200kB to about 200 MB.

The infusion pump 12 may include a power charging mechanism, such as aUSB port, induction charger, or the like. The power charging system maybe used to charge a power storage cell such as a rechargeable battery ofthe infusion pump 12. Some embodiments may use a rechargeable batterysuch as a NiCad battery, LiPo battery or NiMH battery. In someembodiments, the power charging mechanism 56 of the infusion pump 12depicted in FIG. 2 may be a USB port. As such, all data may be kept inthe infusion pump 12 for quick and easy downloading of data to acomputer, other infusion pump device, network etc. using the USB port.The USB port 56 of the infusion pump 12 may also provide the infusionpump 12 with power charging. In some instances, the power chargingmechanism of the infusion pump 12 may be an induction-charging device.In some cases, an advantage of having interchangeable infusion pumpdevices may be that while one infusion pump device is being used forinfusion, the other infusion pump device can be charging.

The infusion pump 12 may also include programming to allow a processorto set therapeutic parameters and control the overall operation of theinfusion pump 12. The therapeutic parameters may include a basal raterange, a bolus volume range, a max bolus volume range, and insulinsensitivity. The processor may include one or more infusion cartridge 16sensing functionalities, which may allow the processor to receive datafrom various sources. The processor may collate data, parse the same,calculate a volume of a fluid disposed in the drug delivery reservoir ordetect the reservoir capacity of the infusion cartridge 16 and may settherapeutic parameters for an infusion cycle. For example, the processormay receive input data from one or more pressure sensors which may beused for setting therapeutic parameters.

FIG. 3 illustrates a block diagram of some of the features that may beincorporated within the housing 26 of the infusion pump 12. The infusionpump 12 can include the memory device 30, the transmitter/receiver 32,an alarm 34, a speaker 36, a clock/timer 38, the input device 40, theprocessor 42, the user interface that may be GUI 60 having a touchsensitive screen 46 with input capability, a drive mechanism 48, and anestimator device 52. The memory device 30 may be coupled to theprocessor 42 to receive and store input data and to communicate thatdata to the processor 42. The input data may include user input data andnon-user/sensor input data. The input data from the memory device 30 maybe used to generate therapeutic parameters for the infusion pump device12. The GUI 60 may be configured for displaying a request for the userto input data and for receiving user input data in response to therequest, and communicating that data to the memory.

The infusion pump 12 includes the processor 42 that functions to controlthe overall functions of the device. The processor 42 may communicatewith and/or otherwise control the drive mechanism, output/display,memory, transmitter/receiver, and the like. The processor 42 of someembodiments of the infusion pump 12 may communicate with a processor ofanother device, for example, a radio-frequency identification (RFID)reader through the transmitter/receiver. The processor 42 may includeprogramming that can be run to control the infusion of insulin or othermedicament from the cartridge, the data to be displayed by the display,the data to be transmitted via the transmitter, etc. The processor 42may also include programming that may allow the processor to receivesignals and/or other data from an input device, such as a sensor thatmay sense pressure, temperature, a continuous glucose monitor and othersimilar devices. The processor 42 may determine the capacity of the drugdelivery reservoir and/or the volume of fluid disposed in the drugdelivery reservoir and may set therapeutic parameters based on itsdetermination.

As discussed above the housing 26 of the infusion pump 12 may befunctionally associated with an interchangeable and a removable glucosemeter 20 and/or infusion cartridge 16. The infusion cartridge 16 mayhave an outlet port 54 that may be connected to an infusion set (notshown) via an infusion set connector 18 (see FIG. 5).

The processor 42 may also include additional programming to allow theprocessor 42 to learn user preferences and/or user characteristicsand/or user history data to, for example, implement changes in use,suggestions based on detected trends, such as, weight gain or loss, andmay include programming that allows the device to generate reports, suchas reports based upon user history, compliance, trending, and/or othersuch data. Additionally, infusion pump embodiments of the disclosure mayinclude a “power off” or “suspend” function for suspending one or morefunctions of the device, such as, suspending a delivery protocol, and/orfor powering off the device or the delivery mechanism thereof. For someembodiments, two or more processors may be used for controller functionsof the infusion pumps, including a high power processor and a low powerprocessor used to maintain programming and pumping functions in lowpower mode, in order to save battery life.

Referring to FIG. 4, a front view of the infusion pump 12 is shown. Theinfusion pump 12 may include a user-friendly GUI 60 on a front surface58 of the infusion pump 12. The GUI 60 may include the touch sensitivescreen 46 that may be configured to display a variety of screens usedfor displaying data, facilitating data entry by a patient, providingvisual tutorials, as well as other interface features that may be usefulto the patient operating the infusion pump 12.

FIG. 5 depicts the infusion pump system 100 with the infusion cartridge16 detached from the infusion pump 12. The infusion pump 12 may includean attachment mechanism 64 positioned within a first receiving slot 22that corresponds to a receiving mechanism 62 at an end of the infusioncartridge 16. The attachment and receiving mechanisms may be configuredto removably couple an interior volume of the cartridge with a volume ofthe pump that may be sealed from the surrounding environment with thecoupling able to retain a fluid within the volumes even undersignificant pressure. The attachment may be so configured and suitablefor producing a leak free detachable coupling that can withstandsignificant pressure. The infusion cartridge 16 may be removablyattached to the housing 26 of the infusion pump 12 for fluid delivery.In this embodiment, the attachment mechanism 64 may include a pneumatictap 66 having an O-ring or other sealing device. The correspondingreceiving mechanism 62 positioned on an end of the infusion cartridge 16may include a port through which the pneumatic tap 66 may be inserted. Areservoir fill port 76 may be disposed on a top portion of the infusioncartridge 16. In some cases, the desired fluid may be manually dispensedfrom the interior volume of a syringe or other device, through thereservoir fill port 76 into the interior volume of the infusioncartridge 16.

Referring to FIGS. 6-7, a collapsible fluid reservoir 68 of the infusioncartridge 16 may be bounded by or disposed within a flexible membrane orlayer 72. The collapsible fluid reservoir 68 may include an interiorvolume 74 in fluid communication with a reservoir inlet port 108 of anaxial bore 104 of a delivery mechanism 120. A top portion of thecollapsible fluid reservoir 68 may be clamped or otherwise sealed to anextension or a boss 82 of the reservoir inlet port 108 that may extendinto a first interior volume 80. In this configuration, the interiorvolume 74 of the collapsible fluid reservoir 68 may be isolated orsealed from the surrounding environment except for the reservoir inletport 108, which may be in fluid communication with the axial bore 104 ofthe delivery mechanism 120.

A substantially rigid shell 86 may be disposed about the collapsiblefluid reservoir 68 with a first interior volume 80 that may contain thecollapsible fluid reservoir 68. The first interior volume 80 of theinfusion cartridge 16 may be disposed between the outer surface 88 ofthe flexible membrane 72 and an interior surface 90 of the rigid shell86. A vent inlet port 112 may be in fluid communication with the firstinterior volume 80 and the axial bore 104 of the delivery mechanism 120.The GUI 60 of FIG. 2 may be operatively coupled to a controller 50,which may include at least one processor 42, a memory device 30, andconnective circuitry or other data conduits that couple the datagenerating and data managing components of the device. A power storagecell in the form of a battery 98 may be rechargeable and may also bedisposed within the housing 26. Data generating or managing componentsof the device may include the processor(s) 42, the memory device 30, theGUI 60, a plurality of sensors including pressure sensors, temperaturesensors, optical sensors, mechanical sensors and the like. Othercomponents such as a vibratory motor 96, the speaker 36, the battery 98,and an electric motor 170 of the drive mechanism 48 may also beoperatively coupled to the controller 50. Connective circuitry mayinclude conductive wiring such as copper wiring, fiber optic conduits.RF conduits and the like.

With reference again to the infusion cartridge 16 generally shown inFIG. 6, the vent inlet port 112 may be disposed on the deliverymechanism 120 in fluid communication with the first interior volume 80disposed between the outside surface 88 of the flexible material ormembrane 72 of the collapsible fluid reservoir 68 and the inside surface90 of the substantially rigid shell or case 86 of the infusion cartridge16. The controller 50 may be coupled to at least one pressure sensor 92which may be disposed in communication with a chamber 94 which may be incommunication with the first interior volume 80 by means of attachmentmechanism 64 and receiving mechanism 62. The controller 50 may beconfigured to generate signals to the drive mechanism 48 to displace thespool 106 of the delivery mechanism 120 based on a reading of thepressure sensor 92.

FIG. 7 depicts a portion of the infusion cartridge 16 including thedelivery mechanism 120, as well as a portion of the drive mechanism 48of the infusion pump 12. The delivery mechanism 120 may be configured todeliver fluid from the collapsible fluid reservoir 68 via a collapsibleor variable volume element of the spool 106. For the embodimentsdiscussed herein, the variable volume elements may include constrainedvariable volume elements that may be mechanically constrained to varybetween a minimum volume and a maximum volume. The delivery mechanism120 may include a delivery mechanism body 102, or housing, and an axialbore 104 disposed in the delivery mechanism body 102. The axial bore104, may have a substantially round transverse cross section andincludes a distal end 144, a proximal end 148 disposed towards the drivemechanism 48 of the infusion pump system 100, a reservoir inlet port108, a fluid outlet port 114, a vent inlet port 112, and a vent outletport 116. The spool 106, may also have a substantially round transversecross section and may be slidingly disposed within the axial bore 104 toform a constrained variable volume 122 and a second sealed volume 154with the axial bore 104.

The constrained variable volume 122 of the delivery mechanism 120 may bepositionable to overlap the reservoir inlet port 108 independent of anoverlap of the fluid outlet port 114. The constrained variable volume122 may be formed between a first seal 140 around the spool 106, asecond seal 142 around the spool 106, an outer surface of the spool bodybetween the first and second seal 140 and 142 and an interior surface ofthe axial bore 104 between the first and second seal 140 and 142. Thefirst and second seals 140 and 142 may be axially moveable relative toeach other so as to decrease/increase a volume of the constrainedvariable volume 122, as when the first and second seals 140 and 142 moveaway from each other, decreasing the constrained variable volume 122, orwhen the first and second seals 140 and 142 may move closer together,increasing the variable volume 122.

The second seal 142 may be disposed on a proximal section 134 of thespool 106 and may move in conjunction with movement of the proximalsection 134 of the spool 106. A proximal end of the spool 136 may becoupled to a ball portion 178 of a drive shaft 176 of the drivemechanism 48 of the infusion pump 12. The drive mechanism 48 includes arack and pinion mechanism 174 actuated by an electric motor 170 througha gear box 172. As such, the second seal 142 may move or translateaxially in step with axial translation of the spool 106 and drive shaft176. The first seal 140, however, may be disposed on a distal section128 of the spool 106, which may be axially displaceable with respect tothe main section 190 of the spool 106. The distal section 128 of thespool 106 may be coupled to the main section of the spool by an axialextension 156 that may be mechanically captured by a cavity 158 in themain section 132 of the spool 106. This configuration may allow apredetermined amount of controlled axial movement between the distalsection 128 of the spool and the main section 132 of the spool 106 andmay translate the constrained variable volume 122 from the reservoirinlet port 108 to the fluid outlet port 114. This configuration mayexpand or contract the constrained variable volume 122 of the spool 106by exerting translational axial force through a boundary section of theconstrained variable volume 122;

For some embodiments, a volume of a “bucket” of fluid dispensed by acomplete and full dispense cycle of the spool 106 may be approximatelyequal to the cross-sectional area of the axial bore 104 multiplied bythe length of displacement of the captured axial extension of the spoolfor the distal section 128. The complete bucket of fluid may also bedispensed in smaller sub-volumes increments, as small as a resolution ofthe drive mechanism 48 allows. For some embodiments, a dispense volumeor bucket defined by the constrained variable volume 122 of the deliverymechanism 120 may be divided into about 10 to about 100 sub-volumes tobe delivered or dispensed. In some cases, the maximum axial displacementbetween the distal section 128 and main section of the spool 132 may beabout 0.01 inch to about 0.04 inch, and, more specifically, about 0.018inch to about 0.022 inch.

For some embodiments, the axial bore 104 of the delivery mechanism mayhave a transverse dimension or diameter of about 0.04 inches to about0.5 inches, and, more specifically, about 0.08 inches to about 0.15inches. For some embodiments, the spool 106 may have a length of about10 mm to about 40 mm, and, more specifically, about 15 mm to about 20mm. The spool 106 and housing of the delivery mechanism 48 may be madefrom any suitable material or materials including polymers or plasticssuch as polycarbonate, PEEK, thermoplastics, cyclic olefin copolymer,and the like. In some cases, the seals disposed on the spool may have anouter transverse dimension or diameter that may be slightly larger thanthat of the spool 106. In some instances, the seals on the spool mayhave an axial thickness of about 0.01 inches to about 0.03 inches andmay be made from materials such as butyl, silicone, polyurethanes or thelike, having a shore hardness of about 65 A to about 75 A, and morespecifically, about 70 A.

In some instances, a second volume 154 of the delivery mechanism 120 maybe formed by the spool 106 and axial bore 104 of the delivery mechanism48. The second volume 154 may be also be formed by a third seal 150disposed around the spool 106 and a fourth seal 152 also disposed aroundthe spool and axially separated from the third seal 150. In someinstances, the axial separation between the third and fourth seals 150and 152, forming the second volume 154, may be greater than the axialseparation between the vent inlet port 112 and the vent outlet port 116of the axial bore 104. The second volume 154 may also be formed by anoutside surface of the spool 106 between the third and fourth seals 150and 152 and an inside surface of the axial bore 104 between the thirdand fourth seals 150 and 152.

The second volume 154 may be axially displaceable with the movement ofthe spool 106, and may also be positionable by such axial displacement,in order to simultaneously overlap the second volume 154 with the ventinlet port 112 and the vent outlet port 116 of the axial bore 104. Suchan overlap of both the vent inlet port 112 and the vent outlet port 116may put these ports in fluid communication with each other and may allowan equilibration of pressure between the first interior volume 80 of theinfusion cartridge 16 and the environment surrounding the vent outletport 116 to vent the interior volume 80. In most cases, the vent outletport 116 may be in communication with the atmosphere and air may passfrom the environment surrounding the vent outlet port 116, through thesecond volume 154 of the axial bore 104 and into the first volume 80, toreplace the fluid dispensed subsequent to the last vent cycle. When thevent inlet port 112 and vent outlet port 116 do not share a commonvolume formed by the spool and axial bore 104 of the delivery mechanism120, they are typically isolated and no venting of the volume takesplace.

In operation, the spool 106 and the volumes formed between the spool106, the axial bore 104 and the circumferential seals 140, 142, 150 and152 disposed on the spool of the delivery mechanism 120 are typicallytranslated in a proximal and distal direction in order to move thevolumes into and out of communication with the various ports of theaxial bore 104. This axial movement in alternating proximal and distaldirections of the spool 106, within the axial bore 104, may be used toput the various ports in fluid communication with translatable volumesof the delivery mechanism 120 and other ports of the mechanism. Forreliable operation, it may be desirable, in some circumstances, for thespool 106 and the circumferential seals 140, 142, 150 and 152 disposedabout the spool 106 to move smoothly within the axial bore 104 of thedelivery mechanism 120, while maintaining a seal between an outsidesurface of the spool 106 and an inside surface of the axial bore 104. Itmay also be desirable for the circumferential seals 140, 142, 150 and152 disposed on the spool 106 to move axially back and forth within theaxial bore 104, while maintaining a seal and with a minimum of friction.Achieving these features of the spool 106 may be facilitated with theuse of particular seal configurations, or gland configurations used tohouse the seals of the spool embodiments.

Referring to FIG. 8A, an elevation view of the infusion cartridge 16 isshown depicting locations of indicia for capacity information. For someembodiments, the infusion cartridge 16, and any of the collapsible fluidreservoir cartridges discussed herein, may include one or more opticallyreadable or detectable indicia, for example, a bar code type stripe 168or a quick response code (QRC) label 166. In some embodiments theoptically detectable indicium may be formed by up to three narrow blanklight reflective stripes 164. The three reflective stripes 164 mayrepresent three bits of data. Each of the light reflective stripes orthe optically readable indicia may be configured to be detected by acorresponding optical reader device of the infusion pump system 100. Insome cases such light reflective stripes may reflect a beam of lightomnidirectionally or unidirectionally.

FIG. 8B is a partial view of the infusion pump device 12 depictinglocations of light sources and various readers. The optical readerdevice may be one of a bar code reader, a QRC reader, an array of photosensors, or a combination of the above along with any other suitablesensors or detectors. In some instances infusion cartridge detection mayrely on continuous readings of the three blank light reflective stripes.For some embodiments, a light source may illuminate one or more of thelight reflecting stripes once the infusion cartridge is properly placedin the infusion pump device. A reflected beam of light from the lightreflecting stripes may hit the photo sensor generating a digital valueof 1 or other suitable indicium. A non-zero digital value may be used toindicate the presence of the infusion cartridge.

For some embodiments, the optical reader device may be in operativecommunication with the controller 50 or processor 42 of the pump. Theencoder device may alternatively be an RFID) tag or the like that maytransmit data to a reader such as a data receiving processor, forexample a RFID reader or the like. Such encoder device embodiments mayinclude the ability to securely transmit and store data, via encryption,to prevent unauthorized access or tampering with such data. Theidentification of the infusion cartridge 16 and its content may be usedby the controller 50 to set or to adjust certain dispense parameters orany other suitable parameters.

Referring now to FIG. 9, a flowchart illustrates a method embodiment 200of setting parameters of an infusion pump such as infusion pump 12.Method 200 may be used to determine the capacity of the collapsiblefluid reservoir and/or the volume of medicine disposed in a collapsiblefluid reservoir and to set delivery/therapeutic parameters of aninfusion pump. Method 200 may start at operation 210, during which aninfusion cartridge 16 containing the collapsible fluid reservoir 68 maybe loaded into the infusion pump 12. In operation 230, data regardingthe capacity of the collapsible fluid reservoir 68 and/or the volume ofmedicine disposed in the collapsible fluid reservoir 68 may be obtainedby using various measurements and sensing techniques as discussed above.In operation 250, the obtained data may be analyzed by a processor 42 todetermine therapeutic parameter settings to be loaded into a memory ofan infusion pump 12 for access by a processor. In operation 270, thetherapeutic parameter setting is loaded into the memory device foraccess by the processor.

Some of the method embodiments described herein may detect/determine thecapacity of the reservoir 68 of the infusion cartridge 16. For someembodiments, the collapsible fluid reservoir 68 may have a volume ofabout 200 units, 300 units, and 500 units. Based on the detectedcapacity of the infusion cartridge 16, therapeutic parameter of theinfusion pump 12 may be set. For example, the basal rate range, thebolus volume, and/or the max bolus volume range may be set lower forinfusion cartridges with a smaller volume than for infusion cartridgeswith a larger volume. Furthermore, patients with high insulinsensitivity (where insulin sensitivity is defined as, units of insulinper mg/dl of blood glucose change) may be treated using a small capacityinsulin cartridge.

FIG. 10 is a flowchart of a method embodiment 330 which depicts variousmeasurements and sensing techniques employed for obtaining sensor data(volume data or capacity data) on the volume of fluid stored in thecollapsible fluid reservoir 68, or a fluid capacity of the infusioncartridge 16 that may be loaded into the infusion pump 12. In operation332, capacity data encoded in an optical code may be obtained by readingthe optical code represented by reflected light using one or moreoptical sensors 126 as discussed above to obtain capacity data or detectthe infusion cartridge 16. In some cases in addition to obtainingcapacity data, a continuous monitoring of the presence of the lightreflective stripes 164 may allow the processor 42 to determine whetherthe infusion cartridge 16 is present in the receiving slots or it hasbeen removed or is inadvertently disconnected.

A method for detecting presence of an infusion cartridge in an infusiondevice can include illuminating the light reflective stripes 164 on theinfusion cartridge 68, detecting reflected light from the reflectingstripes 68, determining whether data represented by the reflected lighthas a predetermined value and generating an audible warning signalindicating absence of a cartridge when data represented by the reflectedlight differs from the predetermined value.

In operation 333, capacity data may be obtained by using a bar codereader to read a bar code strip or a QRC label on the infusioncartridge. In operation 334, capacity data may be obtained by decodingthe positions of switches. The switches may be operated by mechanicalsensors that may be registered with surface grooves or dimples on thecartridge. In some instances, a groove configuration may be used toindicate the fluid capacity of the infusion cartridge 16. In operation335, capacity data may be obtained via a RFID reader. The RFID readermay read an RFID tag that may be affixed to the cartridge. The RFID tagmay store data indicating the capacity of the collapsible fluidreservoir. The RFID reader may be an external or an internal device tothe infusion pump device. In cases where the RFID reader is an externaldevice, the RFID reader data may be wirelessly communicated with theinfusion pump device.

In operation 340, data may be obtained by reading a pressure sensordisposed in the cartridge during consecutive pressure measuring cycles.Changes in the pressure sensor readings may be indicative of the volumeof fluid disposed in the collapsible fluid reservoir. Data on thecapacity of the collapsible fluid reservoir may also be obtained byusing a backstroke volume (V_(backstroke)), which is indicative of thecapacity of the collapsible fluid reservoir 68 if the measurements aretaken when the system is known to be empty of fluid. An example of aV_(backstroke) determination technology is disclosed in U.S. patentapplication Ser. No. 12/714,299 which is incorporated herein byreference in its entirety.

An additional method of determining the identity or size classificationof an infusion pump fluid cartridge may include reading a resistancevalue of a resistor (not shown) that is embedded in the infusioncartridge 16 as is coupled to the processor 42 of the infusion pump 12.The processor 42 may measure a resistance value of the embedded resistorto determine the size of the infusion cartridge 16. For example,different resistor values may indicate infusion cartridges 16 withdifferent sizes of collapsible fluid reservoirs 68. For example, a 10Ohm embedded resistor may indicate an infusion cartridge 16 with a smallsize collapsible fluid reservoir 68 and a 20 Ohm embedded resistor mayindicate an infusion cartridge 16 with a large size collapsible fluidreservoir 68.

FIG. 11 is a flowchart depicting a method embodiment 440 for usingpressure sensor readings to obtain the volume of fluid disposed in thecollapsible fluid reservoir 68. Function-block 450 shows the operationsof the infusion pump 12 for executing a pressure metering cycle. Methodembodiment 440 may start at operation 451. In operation 452, a spool ofan infusion cartridge 16 may be positioned in a fill position. Inoperation 454, a first pressure measurement may be performed in theinterior volume 80. In operation 456, the constrained variable volume122 may be filled with a known amount of fluid removed from thecollapsible fluid reservoir 68. In operation 458, a second pressuremeasurement may be performed in the interior volume 80. In operation460, readings of the first and second pressure measurements may berecorded. In operation 470, the volume of fluid disposed in thecollapsible fluid reservoir 68 may be calculated based on the first andsecond sensor readings. In operation 480, the spool of the infusioncartridge 16 may be positioned in a dispense position. In operation 490,fluid from the constrained variable volume 122 may be dispensed.

FIG. 12 is a flowchart depicting a method embodiment 540 for usingpressure sensor readings to obtain the volume of fluid disposed in thecollapsible fluid reservoir. Method embodiment 540 may start atoperation 542 during which an empty infusion cartridge may be loadedinto the infusion pump 12. In operation 550, a first pressure meteringcycle may be executed. In operation 560, following the pressure meteringcycle, a first pressure sensor reading may be recorded. In operation558, if it is determined that there is another infusion cartridgeavailable, the method may loop back to operation 544 or 548respectively; otherwise, the method may exit in operation 570. Inoperation 544, an infusion cartridge with a known volume of fluid may beloaded into the infusion pump 12 Operation 544 may be followed with asecond execution of the pressure metering cycle 550 and the recording560 of a second pressure sensor reading. In operation 546, a targetinfusion cartridge, i.e. an infusion cartridge that is intended to beused for a present therapy, may be loaded into the infusion device.Operation 548 may be followed with a third execution of the pressuremetering cycle 550, and the recording 560 of a third pressure sensorreading. In operation 570, the volume of fluid disposed in the targetinfusion cartridge may be calculated based on the first, second andthird pressure sensor readings.

Some of the above described method embodiments may detect/determine thecapacity of the collapsible fluid reservoir 68 of the infusion cartridge16. For some embodiments, the collapsible fluid reservoir 68 may have avolume of about 200 units, 300 units, and 500 units. Based on thedetected capacity of the infusion cartridge 16, therapeutic parameter ofthe infusion pump 12 may be set. For example, the basal rate range, thebolus volume, and/or the max bolus volume range may be set lower forinfusion cartridges with a smaller volume than for infusion cartridgeswith a larger volume. Furthermore, patients with high insulinsensitivity (where insulin sensitivity is defined as, units of insulinper mg/dl of blood glucose change) may be treated using a small capacityinsulin cartridge.

Some of the above-described methods may determine the volume of medicinedisposed in the drug delivery reservoir. Based on this volume,therapeutic parameters of the infusion pump may be precisely set oradjusted.

With regard to the above detailed description, like reference numeralsused therein may refer to like elements that may have the same orsimilar dimensions, materials, and configurations. While particularforms of embodiments have been illustrated and described, it will beapparent that various modifications can be made without departing fromthe spirit and scope of the embodiments herein. Accordingly, it is notintended that the invention be limited by the forgoing detaileddescription.

The entirety of each patent, patent application, publication, anddocument referenced herein is hereby incorporated by reference. Citationof the above patents, patent applications, publications and documents isnot an admission that any of the foregoing is pertinent prior art, nordoes it constitute any admission as to the contents or data of thesedocuments.

Modifications may be made to the foregoing embodiments without departingfrom the basic aspects of the technology. Although the technology mayhave been described in substantial detail with reference to one or morespecific embodiments, changes may be made to the embodimentsspecifically disclosed in this application; yet, these modifications andimprovements are within the scope and spirit of the technology. Thetechnology illustratively described suitably herein, may be practiced inthe absence of any element(s) not specifically disclosed herein. Theterms and expressions which have been employed are used as terms ofdescription and not of limitation and use of such terms and expressionsdo not exclude any equivalents of the features shown and described, orportions thereof, and various modifications are possible within thescope of the technology claimed. Although the present technology hasbeen specifically disclosed by representative embodiments and optionalfeatures, modification and variation of the concepts herein disclosedmay be made, and such modifications and variations may be consideredwithin the scope of this technology.

The invention claimed is:
 1. A method for detecting a capacity of acollapsible fluid reservoir in an infusion cartridge and settingtherapeutic parameters of a portable infusion pump with a processor ofthe portable infusion pump, comprising: obtaining from the infusioncartridge, with the processor, data on a capacity of the collapsiblefluid reservoir when the infusion cartridge is loaded into the portableinfusion pump; analyzing, with the processor, the obtained data on thecapacity of the collapsible fluid reservoir to determine the capacity ofthe collapsible fluid reservoir; and determining and setting with theprocessor, prior to delivering therapy using the infusion cartridge, oneor more therapeutic parameters of the infusion pump based on thecapacity of the collapsible fluid reservoir, wherein determining andsetting one or more therapeutic parameters of the infusion pump based onthe capacity of the collapsible fluid reservoir determines and setsparameters at lower values for reservoirs having lower capacities and athigher values for reservoirs having higher capacities.
 2. The method ofclaim 1, wherein setting a therapeutic parameter includes setting abasal rate range.
 3. The method of claim 1, wherein setting atherapeutic parameter includes setting a bolus volume range.
 4. Themethod of claim 1, wherein setting a therapeutic parameter includessetting a maximum bolus volume range.
 5. The method of claim 1, whereinsetting a therapeutic parameter includes setting an insulin sensitivity.6. The method of claim 1, wherein obtaining data on the capacity of thecollapsible fluid reservoir includes illuminating optical indicia on theinfusion cartridge.
 7. The method of claim 6, further including readingan optical code on the infusion cartridge that indicates the capacity ofthe collapsible fluid reservoir with an optical sensor.
 8. The method ofclaim 7, wherein the optical code on the infusion cartridge is obtainedfrom omnidirectionally reflecting stripes.
 9. The method of claim 7,wherein the optical code on the infusion cartridge is obtained fromunidirectionally reflecting stripes.
 10. The method of claim 6, furtherincluding reading a bar code on the infusion cartridge.
 11. The methodof claim 6, further including reading a quick response code on theinfusion cartridge.
 12. The method of claim 1, wherein obtaining data onthe capacity of the collapsible fluid reservoir includes sensingpositions of a plurality of switches coupled to mechanical sensors ofthe infusion pump that are registered with surface grooves on theinfusion cartridge indicating the capacity of the collapsible fluidreservoir.
 13. The method of claim 1, wherein obtaining data on thecapacity of the collapsible fluid reservoir includes a reading of aradio-frequency identification (RFID) tag affixed on the infusioncartridge, the RFID tag adapted to store data regarding the capacity ofthe collapsible fluid reservoir.
 14. The method of claim 13, wherein areading of the RFID tag is performed by an RFID reader, which isexternal to the infusion pump.
 15. The method of claim 14, wherein thereading of the RFID reader is wirelessly communicated to the infusionpump.
 16. The method of claim 13, wherein the reading of the RFID tag isperformed by an RFID reader, which is secured to the infusion pump.